This invention relates to rotorcraft rotors and, more particularly, to a rotor blade mounting assembly.
A helicopter rotor hub is the primary structural assembly for driving torque to each rotor blade, balancing centrifugal loads between opposing rotor blades and transferring lift loads to the aircraft fuselage. Within the class of articulated rotors are those which include a rotor yoke, one per rotor blade, which is driven by a central hub plate via a multi-laminate elastomeric bearing. The dimensions of the rotor yoke are determined by the operational motion envelope of the rotor system and blade loads.
Historically, helicopter rotor hubs and their associated parts have been made of high strength, lightweight, critical metals or alloys. Although these metal components perform adequately, it is always desirable to reduce the empty weight of the helicopter. Presently, titanium and aluminum are used extensively because of their generally light weight and strength. There is a constant search for lighter and stronger materials. One consideration for decreasing the empty weight of the helicopter is to use fiber reinforced composites to replace metal components. However, the cost of a composite part, especially a part requiring a significant number of plies, is often not competitive with the comparable metal part that it is designed to replace.